The relationship status of a group of Chinese Han college students may be determined, in part, by their DNA, suggests a study in Scientific Reports this week. Romantic behaviours have been associated with levels of serotonin in the brain, and the new study indicates that different versions of genes for a serotonin receptor are linked to likelihood of being in a relationship. However, the authors caution that it is unclear whether the findings might be replicated in other groups of people, and they explain that other factors, such as social and personal attributes, could overshadow the apparent genetic contribution to romantic relationship formation.
Xiaolin Zhou and colleagues investigate the effects of variation in the gene that codes for 5-HT1A - a receptor that lowers levels of serotonin - in 579 Chinese Han senior college students. Specifically, they look at two variants of a version known as polymorphism C-1019G: the G allele, which increases levels of 5-HT1A, relative to another variant called the C allele. The authors show that possessing one or two copies of the G allele is associated with a lower likelihood of individuals being in a relationship. They report that 50.4% of individuals with two copies of the C allele were in a relationship compared with 39.0% of individuals with either one or two copies of the G allele. The association seems to hold even after taking into consideration other factors that influence relationships, such as socioeconomic status, external appearance, religious beliefs, parenting style and depressive symptoms.
The authors emphasize that students in college have strong motivations to engage in relationships. They note that in other situations, at least in Chinese society, family and social pressures might affect the development of relationships, and it is not clear if the association between the 5-HT1A gene and relationship status would hold.